Psoriasis causes and treatment

Doctors and scientists don't know exactly what causes psoriasis. But they do know that one type of immune system cells, known as T cells, plays a role. In psoriasis, something tells certain T cells to move to the skin and behave as though they are fighting an infection. This leads to inflammation (redness and irritation) and increased production of skin cells. The excess skin cells form a dead, scaly layer called a plaque on top of the psoriasis lesion. All of these factors contribute to the symptoms of psoriasis. Psoriasis is also at least partly genetic.

There are many different types of psoriasis treatment, but many treatments work in a similar way: by reducing the activity of the immune system. This decreases symptoms by fighting inflammation and skin cell overgrowth.

The choice of treatment for psoriasis depends on the type and severity of the psoriasis, where the psoriasis is found on the body, the person's general health, and other medications the person may be taking. The main psoriasis treatments are:

  • Topical medications: These medications are applied to the skin areas affected by psoriasis. These treatments are used for mild to moderate cases of psoriasis, or in combination with other treatment options.
  • Systemic medications: This group includes medications taken by mouth (oral medications) and by injection (injectable medications). Injectable medications may be biologics or non-biologics (such as methotrexate injections).
  • Phototherapy: This treatment uses ultraviolet light to reduce psoriasis symptoms. It is used for moderate to severe cases of psoriasis.
  • Biologics: These are injectable medications that are used for moderate to severe cases of psoriasis.

Find out more about how each treatment type works in the following sections on topical treatments, phototherapy and oral medications, and biologics.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/healthfeature/gethealthfeature/Psoriasis-How-Treatment-Works

How do topical treatments work?

 
Topical treatments are applied to the skin areas that are affected by psoriasis. They act directly in the area where they are applied. There are many different topical treatments - here's how they work:

  • Topical corticosteroids work by controlling skin cell overgrowth and reducing inflammation.
  • Calcipotriol is a form of vitamin D. It works by slowing down skin cell overgrowth.
  • Salicylic acid helps get rid of psoriasis plaques by breaking down the dead skin cells on top of the psoriasis lesion.
  • Tazarotene is a synthetic form of vitamin A. Scientists do not know exactly how it works. However, it is believed to decrease skin cell growth and also increase breakdown of the dead skin cells in the psoriasis plaques.
  • Coal tar works by slowing down skin cell production.
  • Anthralin works by decreasing the growth of skin cells.

In general, the effects of topical treatments do not last once the treatment is stopped. Once treatment is stopped, the symptoms can return again. Topical treatments may be used alone, in combination with one another, or in combination with systemic therapy or light therapy.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/healthfeature/gethealthfeature/Psoriasis-How-Treatment-Works

How do oral medications and light therapy work?

 
There are three oral (taken by mouth) medications available in Canada for psoriasis treatment: methotrexate, cyclosporine, and acetretin. They are used for severe psoriasis. Here's how they work:

  • Methotrexate and cyclosporine both belong to a group of medications known as immunosuppressants. They work by decreasing the overall activity of the immune system. Methotrexate may also be given by injection.
  • Acetretin is a synthetic form of vitamin A. It's not understood exactly how it works, but it is believed to restore a more normal pattern of cell growth in the skin. It may also decrease skin inflammation and make psoriasis lesions less thick and scaly.

Light therapy is believed to work by decreasing skin cell overgrowth and possibly by decreasing the immune system activity that leads to skin cell overgrowth. It is used for moderate to severe psoriasis. Light therapy is given by a qualified dermatologist, who shines ultraviolet light on the parts of the skin affected by psoriasis (the lesions).

Medications known as psoralens may be used in combination with light therapy to make the skin more sensitive to the light and thus increase the effects of treatment. Unlike oral medications, light therapy can target specific areas of the skin, depending on where the doctor shines the light. Treatment sessions are usually given twice weekly, and it takes 4-10 treatment sessions for the therapy to work.

Once oral medications or light therapy are stopped, the psoriasis symptoms can return.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/healthfeature/gethealthfeature/Psoriasis-How-Treatment-Works

How do biologics work?

Biologics are a new type of psoriasis medication made from proteins produced by living human and animal cells. Biologics work by targeting the underlying cause of psoriasis. They act on specific areas of the immune system that are overactive in people who have psoriasis. Some biologics work by stopping T cells, a major contributing factor in psoriasis, from becoming activated and/or from migrating to the skin, or by reducing the number of activated T cells. Biologics can also work by blocking immune system messengers that play a role in the overproduction of skin cells.

What makes biologics different from other psoriasis treatments? Most oral psoriasis drugs work by decreasing the activity of the immune system in general. This is called immunosuppression, and can lead to an increased risk of infection, liver damage, or kidney damage. Biologics are different because they only work on those parts of the immune system that are overactive. This means they may have a lower risk of infections and side effects in other organs when compared with immunosuppressants.

There is another important difference between biologics and other psoriasis treatments. With biologics that inhibit T cells that cause psoriasis, treatment effects can last even after the drug is stopped. Relief of symptoms that continues after the drug is stopped is called a "remission." It means that people with psoriasis may take a break from drug treatment - this is called a "drug holiday." With other types of psoriasis drugs, the symptoms can return once the drug is stopped. When a drug is used continuously to keep symptoms at bay, this is known as "suppression."

Alefacept is the first biologic available in Canada for the treatment of psoriasis. It is used in people with moderate to severe chronic plaque psoriasis who are candidates for phototherapy or systemic therapy. It is believed to work by preventing T cell activation and by decreasing the numbers of activated T cells. Alefacept is given by intramuscular (into a muscle) injection once weekly for 12 weeks, followed by a treatment-free period of at least 12 weeks. About 7 out of 10 people notice a meaningful improvement in symptoms after 2 courses of treatment. The improvement usually lasts for about 7-8 months after treatment is stopped, which means that long treatment-free periods are possible. For more information about biologics, contact your dermatologist.

All material copyright MediResource Inc. 1996 – 2021. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/healthfeature/gethealthfeature/Psoriasis-How-Treatment-Works